Cognitive radio based spectrum assignment for heterogeneous multicast terrestrial communication systems with different transmission rate requirements

Author(s):  
M. Yang ◽  
D. Grace
Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4142
Author(s):  
Peiyuan Si ◽  
Weidang Lu ◽  
Kecai Gu ◽  
Xin Liu ◽  
Bo Li ◽  
...  

As wireless communication technology keeps progressing, people’s requirements for wireless communication quality are getting higher and higher. Wireless communication brings convenience, but also causes some problems. On the one hand, the traditional static and fixed spectrum allocation strategy leads to high wastefulness of spectrum resources. The direction of improving the utility of spectrum resources by combining the advantages of cooperative communication and cognitive radio has attracted the attention of many scholars. On the other hand, security of communication is becoming an important issue because of the broadcasting nature and openness of wireless communication. Physical-layer security has been brought into focus due to the possibility of improving the security in wireless communication. In this paper, we propose an anti-wiretap spectrum-sharing scheme for cooperative cognitive radio communication systems which can secure the information transmission for the two transmission phases of the cooperative communication. We maximized the secondary system transmission rate by jointly optimizing power and bandwidth while ensuring the primary system achieves its secrecy transmission rate. Useful insights of the proposed anti-wiretap spectrum-sharing scheme are given in the simulation results. Moreover, several system parameters are shown to have a big impact for the simulation results.


2011 ◽  
Vol 33 (7) ◽  
pp. 1561-1567 ◽  
Author(s):  
Xiao-fei Wang ◽  
Yue-bing Chen ◽  
Xi Zhang ◽  
Quan Zhang ◽  
Chao-jing Tang

2021 ◽  
Author(s):  
Zhiming He

This thesis considers the radio resource management (RRM) of advanced wireless communication systems. With the emerging of more advanced and more complicated systems, such as cognitive radio, nodes with energy harvesting capacities (green communications), and the application of Multiple-Input Multiple-Output (MIMO) technology, RRM problems introduce more difficulties and challenges to optimize system performances. Due to specific structure of communication systems, water-filling (WF) plays an important role in RRM. This thesis introduces the fundamental theory and development of WF algorithm. The proposed Geometric Water-Filling (GWF) is presented and compared with the conventional WF algorithms. It can break through the limitations of the conventional WF to solve the more complicated optimization problems in the advanced wireless communication systems. For the application of the proposed GWF to solve the RRM problems in the advanced MIMO communication systems, cognitive radio communication systems, green communication systems and the “dual problems”, which are the sum power minimization problems, of the throughput maximization problems is investigated in this thesis. Efficient algorithms are presented to achieve the optimal resource allocation.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Riqing Chen ◽  
Jun Wang ◽  
Ruiquan Lin ◽  
Xiangning Zhao

Cognitive radio is regarded as a core technology to support wireless information systems. Spectrum sensing is one of the key steps to achieve cognitive radio technology. To address this problem in the presence of Alpha stable noise in wireless communication systems, we propose a nonparametric autocorrelation method, which takes advantages of the characteristics of signal autocorrelation and noise nonstationarity. The autocorrelated signal is distinguished from Alpha stable noise. As a result, the proposed method is immune from noise uncertainty. Simulation results show the validity of the proposed method under Alpha stable noise, for example, impulsive noise in wireless information systems.


Author(s):  
В.Л. Мартынов ◽  
В.И. Дорошенко ◽  
Н.М. Божук ◽  
Ю.Г. Ксенофонтов

Решению вопросов, связанных с телекоммуникационным оборудованием, функционирующем в водной среде, в настоящее время уделяется особое внимание. На смену традиционным подводным системам обмена информацией в гидроакустических полях приходят открытые системы её оптической передачи и приёма, базирующиеся на лазерных технологиях. Это вызвано необходимостью трансляции с высокой разрешающей способностью видеоданных, среди которых, например, может быть либо визуальное отображение подводных систем в динамике, либо результаты мониторинга объектов подводной инфраструктуры в реальном масштабе времени, либо что-то другое с учётом требований Заказчика. Канал передачи такого большого объёма информации при условии ее считывания с задаваемым качеством должен иметь пропускную способность более 1 Мбит/с. Такую высокую скорость передачи невозможно реализовать в подводных гидроакустических системах, граница технических возможностей которых на превышает 10...50 кбит/с. В аналогичной ситуации при заданных параметрах канала связи частоты несущих оптического диапазона имеют порядок 1014 Гц, что обеспечивает динамический диапазон полосы пропускания в районе 1012…1013 Гц. С учётом условия квазимонохроматичности применение гидроакустических средств для передачи видеоданных становится проблематичным, так как техническая реализация такой задачи потребует слишком большого времени. С учётом сказанного, преимуществом подводных беспроводных оптических систем связи является их высокая широкополосность, которая обеспечит высокую скорость передачи данных. В статье обосновывается целесообразность использования открытых оптических системы связи для создания высокоскоростных подводных инфотелекоммуникаций, среди которых наиболее предпочтительными являются лазерные системы. Special attention is currently paid to the solution of issues related to telecommunication equipment operating in the aquatic environment. The traditional underwater systems for the exchange of information in hydroacoustic fields are being replaced by open systems for its optical transmission and reception, based on laser technologies.This is due to the need to broadcast high-resolution video data, among which, for example, there can be either a visual display of underwater systems in dynamics, or the results of monitoring objects of underwater infrastructure in real time, or something else, taking into account the requirements of the Customer. The transmission channel of such a large amount of information, provided it is read with a specified quality, must have a bandwidth of more than 1 Mbit / s. Such a high transmission rate cannot be realized in underwater sonar systems, the technical capabilities limit of which does not exceed 10 ... 50 kbit/s. In a similar situation, given the parameters of the communication channel, the carrier frequencies of the optical range are 1014 Hz, which provides a dynamic bandwidth range about 1012…1013Hz. Taking into account the condition of quasimonochromaticity, the use of hydroacoustic means for transmitting video data becomes problematic, since the technical implementation of such a task will take too long. In view of the above, the advantage of underwater wireless optical communication systems is their high broadband, which will provide a high data transfer rate. The article substantiates the expediency of using open optical communication systems for creating high-speed underwater information telecommunications, among which the most preferable are laser systems.


2015 ◽  
Vol 2015 ◽  
pp. 1-14
Author(s):  
Dawei Wang ◽  
Pinyi Ren ◽  
Qinghe Du ◽  
Li Sun ◽  
Yichen Wang

Aiming at allocating more licensed spectrum to wireless sensor nodes (SNs) under the constraint of the information security requirement of the primary system, in this paper, we propose a cooperative relaying and jamming secure transmission (CRJS) scheme in which SNs will relay primary message and jam primary eavesdrop concurrently with SN’s downlink and uplink information transmission in cognitive radio sensor networks (CRSNs). In our proposed CRJS scheme, SNs take advantages of physical layer secure technologies to protect the primary transmission and acquire some interference-free licensed spectrum as a reward. In addition, both decode-and-forward (DF) and amplify-and-forward (AF) relaying protocols are investigated in our proposed CRJS scheme. Our object is to maximize the transmission rate of SNs by optimal allocating of the relaying power, jamming power, and downlink and uplink transmit power under the target secure transmission rate requirement of the primary system. Moreover, two suboptimal algorithms are proposed to deal with these optimization problems. Furthermore, we analyze the transmission rate of SNs and allocate the relaying power, jamming power, and downlink and uplink transmit power for the asymptotic scenarios. Simulation results demonstrate the performance superiority of our developed strategy over conventional jamming scheme in terms of the transmission rate of WSN.


2021 ◽  
Author(s):  
Zhiming He

This thesis considers the radio resource management (RRM) of advanced wireless communication systems. With the emerging of more advanced and more complicated systems, such as cognitive radio, nodes with energy harvesting capacities (green communications), and the application of Multiple-Input Multiple-Output (MIMO) technology, RRM problems introduce more difficulties and challenges to optimize system performances. Due to specific structure of communication systems, water-filling (WF) plays an important role in RRM. This thesis introduces the fundamental theory and development of WF algorithm. The proposed Geometric Water-Filling (GWF) is presented and compared with the conventional WF algorithms. It can break through the limitations of the conventional WF to solve the more complicated optimization problems in the advanced wireless communication systems. For the application of the proposed GWF to solve the RRM problems in the advanced MIMO communication systems, cognitive radio communication systems, green communication systems and the “dual problems”, which are the sum power minimization problems, of the throughput maximization problems is investigated in this thesis. Efficient algorithms are presented to achieve the optimal resource allocation.


2019 ◽  
Vol 16 (6) ◽  
pp. 129-149
Author(s):  
Prabhat Thakur ◽  
Alok Kumar ◽  
S Pandit ◽  
G Singh ◽  
S N Satashia

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